Disease relevance of Tyr-arg

• The kyotorphin stimulation of low Km GTPase was abolished by pretreating membranes with islet-activating protein, pertussis toxin, and was recovered by reconstitution with purified G-protein, Gi, but not with Go [1].
• 2. Subcutaneous administration of L-arginine (100-1,000 mg kg-1), a possible precursor of kyotorphin which is an endogenous analgesic neuropeptide, inhibited carrageenin-induced hyperalgesia in a dose-dependent manner [2].
• A novel method for the synthesis of kyotorphin, Tyr-Arg, and 3H-Tyr-Arg, catalyzed by tyrosyl-tRNA synthetase from Bacillus stearothermophilus [3].
• A TRH neuronal system in the brain may explain the mechanism of kyotorphin-induced hypothermia [4].
• Seizure-protecting effects of kyotorphin and related peptides in an animal model of epilepsy [5].

Psychiatry related information on Tyr-arg

• Cyclo(N-methyl-L-Tyrosine-L-Arginine) (cyclo NMTA), an analogue of kyotorphin, increased the reaction time in the tail-pressure and tail-flick tests [6].
• The effects of kyotorphin (KTP), a dipeptide (L-Tyr-L-Arg), on the level of sensory attention to stimuli of different modalities in rats and the exploratory behavior in goldfish were investigated [7].

High impact information on Tyr-arg

• Purification of a novel type of calcium-activated neutral protease from rat brain. Possible involvement in production of the neuropeptide kyotorphin from calpastatin fragments [8].
• Kyotorphin (tyrosine-arginine) synthetase in rat brain synaptosomes [9].
• The site of action of kyotorphin-induced responses was identified to be on nociceptor endings, because the responses were markedly attenuated by intrathecal pretreatments with Galpha(i1) or Galpha(i2) antisense-oligodeoxynucleotides [10].
• The antinociceptive effects of all these new Trp(Nps)-containing dipeptides were evaluated after icv administration in mice, and the effects were compared with those of 1b, 2b, Tyr-Arg (Kyotorphin), and Tyr-D-Arg [11].
• In view of the structure-activity relationships obtained, several similarities between this series of Trp(Nps)-containing dipeptides and that of Kyotorphin analogues have emerged [11].

Biological context of Tyr-arg

• The effects of kyotorphin and the synthetic analogue, D-kyotorphin, on cholinergic fast excitatory postsynaptic potentials (fast-e.p.s.ps) were studied using intracellular recordings from bullfrog sympathetic ganglion cells [12].
• The present study demonstrates a potent action of kyotorphin and its analog on thermoregulation [4].
• The hypothermia induced by kyotorphin, its cyclic analog and Met-ENK was prevented by a small dose of TRH (0.18 microgram = 0.5 nmol/animal) which by itself had little effect on body temperature [4].
• An enkephalin-degrading aminopeptidase from rat brain catalyzes the hydrolysis of a neuropeptide, kyotorphin (L-Tyr-L-Arg) [13].
• Effects of central injection of kyotorphin and L-arginine on oxytocin and vasopressin release and blood pressure in conscious rats [14].

Anatomical context of Tyr-arg

• We have found a novel type of Ca2(+)-activated neutral protease in rat brain cytosol which cleaves -Tyr-Arg-containing calpastatin fragments to release the neuropeptide kyotorphin [8].
• Effect of the endogenous analgesic dipeptide, kyotorphin, on transmitter release in sympathetic ganglia [12].
• Similar effects of kyotorphin were seen in the spinal cord preparations [15].
• Kyotorphin synthetase activity in rat adrenal glands and spinal cord [16].
• Kyotorphin has a novel action on rat cardiac muscle [17].

Associations of Tyr-arg with other chemical compounds

• In rat cerebellar cytosol, the binding activity of [3H]NG-nitro-L-arginine (NNA) was inhibited equally by L-arginine (L-Arg), kyotorphin, and L-leucyl-L-Arg (a kyotorphin receptor antagonist) [18].
• Type II arginase may be an important part of the arginine regulatory system affecting nitric oxide synthase, arginine decarboxylase, kyotorphin synthase, and arginine-glycine transaminase activities and polyamine and proline biosynthesis [19].
• A putative met-enkephalin releaser, kyotorphin enhances intracellular Ca2+ in the synaptosomes [20].
• These findings suggest that the nociceptive effect produced by Tyr(NMe)-Arg-OH in subattomol doses occurs via specific interaction with the kyotorphin receptor and that the extraordinary potency observed may result from amplification through local substance P release [21].
• In the crude soluble extracts from the adrenal glands and spinal cord, kyotorphin was formed by kyotorphin synthetase, and also by the enzymatic processing of the precursor proteins, in the presence of physiological concentrations of L-Tyr and L-Arg in addition to ATP and MgCl2 [16].

Gene context of Tyr-arg

• Low dose of kyotorphin (tyrosine-arginine) induces nociceptive responses through a substance P release from nociceptor endings [22].
• These results suggest that kyotorphin is degraded to L-Arg by KTPases, which in turn may act as substrate for nNOS [18].
• Isolation and identification of an analgesic opioid dipeptide kyotorphin (Tyr-Arg) from bovine brain [23].
• In particular, kyotorphin (Tyr-Arg) completely inhibited Gly-Sar uptake with the K(i) value of 29+/-14 microM [24].
• The effects of a new endogenous opioid dipeptide (Tyr-Arg), kyotorphin, on single unit activities recorded from the lamina V type neurons in the spinal dorsal horn and the neurons in nucleus reticularis paragigantocellularis (NRPG) of the medulla oblongata were investigated in the rabbit and rat, respectively [25].

Analytical, diagnostic and therapeutic context of Tyr-arg

• This effect of kyotorphin may be a possible mechanism related to the manifestation of analgesia [15].
• Using high performance liquid chromatography, we measured kyotorphin content in discrete regions of the rat brain and spinal cord in an attempt to clarify its physiological significance [26].
• Kyotorphin was determined using high-performance liquid chromatography (HPLC) with an electrochemical detector [27].
• The characteristics of kyotorphin (Tyr-Arg)-induced release of Met-enkephalin from the striatum and the spinal cord of guinea pig were determined by superfusing the slices in vitro and then carrying out radioimmunoassays [15].
• Inhibition of theta and alpha rhythms after administration of Asp-Tyr and kyotorphin was more transient than after brain fractions [28].

References